Catalytic gasification of digestate sludge in supercritical water, experimental results on the pilot plant scale

Gasification in supercritical water can be assisted with heterogeneous catalysts. Effective salt separation up stream of the catalyst is important to avoid poisoning of the catalyst and recover nutrients. Recovery of phosphorus, nitrogen and gasification of a significant portion of organic bounded carbon have been demonstrated in the pilot plant scale. A Ru/C catalyst was applied to catalyze the formation of CH4 which should be the primary gasification product. On top of the catalyst a layer of ZnO as sulfur adsorbent was used to protect the catalyst from deactivation. As feedstock for the process glycerol, ethanol and digestate sludge were applied.
Proceedings of the 24th European Biomass Conference and Exhibition, 6-9 June 2016, Amsterdam, The Netherlands, pp. 1062-1066